Coupled cavity type circuits have wide application as interaction circuits in high power traveling wave tubes. They are distinguished by high thermal dissipation capabilities since they are all-metallic and propogate only waveguide modes. Their technology is well established in the art, and they are suitable for economical production in applications up to 20GHz.
Current practice has been to manufacture circuits for the higher frequencies with the same technology used to manufacture circuits for the lower frequencies. This practice results in a highly unsatisfactory dimensional integrity and also in a high scrap factor; the combination of which results in lower efficiency of operation and higher costs of production and operation.
Several manufacturing problems have existed because of the necessity for maintaining very stringent fabrication tolerances during the high temperature brazing of a cavity stack having up to 100 transverse braze joints.